If $x \bigtriangledown y = x(y-7)$ and $x \odot y = 3x-7$, find $(5 \bigtriangledown 6) \odot -5$.
Explanation: First, find $5 \bigtriangledown 6$ $ 5 \bigtriangledown 6 = 5(6-7)$ $ \hphantom{5 \bigtriangledown 6} = -5$ Now, find $-5 \odot -5$ $ -5 \odot -5 = (3)(-5)-7$ $ \hphantom{-5 \odot -5} = -22$.